Lawn-mower sharpener



Feb. 26, 1924; v M 4 79 J. A. GRASSMAN LAWN MOWER SHARPENER Filed Oct.10 1921 3 Sheets-Sheet 1 Febo 26,, 1924. EAMJQB J. A. GRASSMAN LAWNMOWER SHARPENER Filed 001;. 10, 1921 3 Sheets-Sheet 2 Feb 26, 192%1,484,?8

J. A. GRASSMAN LAWN MOWER SHARPENER Filed Oct. 10, 1921 3 Sheets-Sheet 5ifetented Feb. 26,

JOHN ADAM GRASSMAN, OF PALMYRA, PENNSYLVANIA; JOHN ADAM GRASSMAN ALD-MINISTMTOB F SAID JOHN ADAM GRASSMAN, DECEASEJ).

Lawn-Mower. snanrnnna.

Application 'filed October 10, 1921. Serial No. 506,787.

To all whom it may concern: of legs 12 is pivotall connectedto the Be itknown that 1, JOHN ADAM GRASS- frame 11 as at 13, the egs 12 includingre- MAN, a citizen of the United States, and a movable sections 12 and apair of legs resident of Palmyra, in the county of Leb- 1 1 is pivotallyconnected with the legs 12,

anon and State of Pennsylvania, have inby means of a shaft 15, the pairsof legs 60 vented certain new and useful Improvecrossing and the upperends of the pair of ments in Lawn-Mower I Sharpeners, of legs 14engaging the underside of the table which the following is aspecification. v whereby the legs constitute a base upon The presentinvention relates to an imwhich the table or support is mounted. 1oprovement in lawn mower Sharpeners. The lawn mower to be sharpened isdesig- 35 One of the principal objects of the presnated generally at Land may be of any ent invention is to provide an improvementconventional type. Preferably it includes in lawnmower sharpeners whicheffects a a frame 16, rotatable ground or traction proper grinding orsharpening of the cutters wheel 17, a fixed cutter or ledger plate 18,

w of the' revolving reel and of the ledger a rotary cutter of the reeltype including plates or fixed cutter without disassembling a pluralityof cutters 19 and driving mechathese elements and without requiring thenism for the rotary cutter including interexercise of special skill;which is portable nal gears 20 provided on the ground wheels andpossessed of the capacity for the necesand pinions 21 coactingtherewith, the pinsary adjustments; and which is in general ions beingconnected with the shaft 22 of W of simple and durable construction,reliable the rotary cutter by suitable ratchet mechain operation andeasy and inexpensive to nism such as a ratchet 23 and a sliding pawlmanufacture. 24 operating in a transverse slot provided Other objectsand advantages of the inin the cutter shaft 22. The lawn mower 2 ventionreside in certain novel features of also includes an adjustable gaugeroller 25 Q0 construction, combination and arrangement and a handle 26connected with the frame of parts which will be hereinafter more of themachine by a bail 27 fully described and particularly pointed out Priorto mounting the lawn mower on the in the appended claims, referencebeing bad table for the sharpening operation the 30 to the accompanyingdrawings forming ratchet mechanism is reversed so that the 95 part ofthis specification, and in which: rotary cutters will traverse theledger plate Figure 1 is a perspective view of an emin a directionopposite to that in which they bodiment of the invention in use insharpenmove during t e cutting operation. This ing a lawn mower; may beaccomplished by removing the Figure 2 is a similar view, showing theground wheels and the ratchet mecha invention equipped with aconvertible hand nism and placing the ratchet mechanism of or footdrive; one side on the other side of the machine Figure 3 is a groupview in perspective, and vice versa. For instance, the ratchetillustrating the hand drive of Figure 2; mechanism on the right-handside is re- Figure 4 is a similar view of the emery moved and placed onthe left-hand side in- 95 feed board and its support; stead of the usualratchet mechanism pro- Figure 5 is a detail perspective view of videdthere. the emery apron or receiver; v In mounting the lawn mower on thesup- Figure 6 is a view in fragmentary secport, the adjustable gaugeroller 25 is first tion, showing the ratchet mechanism of the set in thelowermost position and is then relawn mower reversed; ceived against aseat provided therefor on Figure 7 is a view in elevation, showing thetable 10 by means of a transverse bar the machine folded up; and 30secured to the table, the mower being- Figure 8 is a fragmentary detailview in balanced or supported on the gauge roller section of thelatching means. by means of a chain or cable 31 engaging the 105Referring to the drawings wherein for the handle 26 of the lawn mowerand releasably sake of illustration is shown the preferred fastened atits ends to the table 10, as clearly embodiment of the invention, thenumeral shown in Figures .1 and 2. Preferably the 10 designates a tableor support having va. means for releasably fastening the chain 111- Iframe 11 on the underside thereof. A pair eludes a chain engagingelement or resilient 1w tudinal slot bracket .32secured to one side ofthe table 10 and selectively cooperable with the links of the chain 31.i

Driving mechanism is provided and as shown in Figure 1, may comprise anadjustable supporting arm 35 having a longi- 36 therein which receivesthe shaft 15 on which the supporting arm is adjustably secured by meansof a washer 37 and nut 38 threaded on the shaft 15. On the outer end ofthe su porting arm a driving pulley 39 is rotatal hly journaled and hasfixed thereto a hand crank or'lever 40 by which the pulley may beturned. It is obvious that a motor may be utilized instead ofthe handcrank, if this is desired. A belt 41 is trained over the driving pulley39 and the overlying traction or groundwheel 17 and constitutes meansfor transmitting the mfithin of the driving pulley to the ground w ee. 1

If desired the driving mechanism shownin Fi re 1 may be removed and theconvertibe hand or foot driving mechanism shown in Figures 2 and 3 maybe employed. This convertible driving mechanism includes a pair ofclamping members 42 having curved clamping fingers 42 provided withsuitable friction surfaces engageable with the ground wheel 17 andhaving confronting arms 42 provided with opposed openings 42 with whicha clamping nut and bolt 43 coaets and opposing bearings 42 in which ahand lever 44 having a removable hand grip 44 is releasably secured bymeans of a set screw 45. These parts of this mechanism constitutes ahand driving mechanism and when it is desired to provide a foot actuateddriving mechanism, the hand grip 44 is removed and one end of a pitman46 is pivotally connected to the hand lever 44, the other end of thepitman being pivotally connected to a treadle frame 47 journaled insuitable bearings 48 provided therefor in the legs 12 and having a footplate 49 secured thereto. When the foot actuated driving mechanism isnot in use the treadle frame 47 is disconnected from the pitman 46 andis received in seats 50 provided in the legs 12 and is held in theseseats by retaming plates 51.

When the hand crank 40, the hand lever 44 or the foot plate 49 of thetreadle is actuated the ground wheel is turned and as the ratchetmechanism is reversed, the rotary cutters are caused to traverse theledg-' er plate in a direction opposite to that 1n whlch they normallymove with respect thereto. This of itself has a sharpening action but inorder to produce a keen edge on both the rotary cutters and the ledgerplate it is proposed to feed a powdered abrasive, such as powderedemery, to the ledger plate so that when the rotary cutters move acrossit, they will carry the powdered emery with the desired edges onincludes telescoping sections 59" weaves them so that it will feed boardonto the ledger plate. -An exv tensible apron or receiver 59 (see Fig.5) and is supported in position by hooks 60 engaging the frame 16 of thelawn mower and extending under the cutters to catch the powdered emeryafter it h'as exerted its grinding action and preserve it so that it maybe utilized over again.

When the apparatus is not in use as a sharpener it may be folded up asshown in Figure 7, with the pair of legs 14 nested within the legs 12and the table 10 and its rame 11 set down in between the legs. Means isprovided for releasably securing the apparatus folded up in this mannerand may comprise a spring latch bar 62 con structed of resilient metaland secured at one end, as at 63, to the underside of the table 10 andloosely mounted at its other end on a stud 64. The latch bar 62 has onlya limited degree of movement on the stud .64 and the head 64* of thisstud constitutes a fulcrum for the latch bar during the releaseoperation, as will presently appear. At the end adjacent the looseconnection 64, the latch bar is offset, as at 65, the outer end of theoffset portionbeing curved or beveled, as

at 65, and the ofl'set portion being provided intermediate its ends withan opening or socket 66 which is adapted to receive a pin 67 carried bythe shaft 15 and coacting with the latch bar to effect the locking ofthe parts in folded position, as shown more especially in Figure 8.Release mechanism is associated with the latch bar and includes aninternally threaded bushing 68 set in the table 10 and a threadedoperatin plug 69 engaged with the bushing and iaving 'a tongue 70adapted to cooperate with a slotted operating tool 71. When it isdesired to release the latchin mechanism, the operating plug is turnedto depress the latch bar 62 and cause it to flex about its fulcrum 64",whereby the offset portion 65 is moved away from the pin 67 to releasethe latch mechanism.

magma then organized with the ground wheel of the lawn mower and theemery feed board and-the emery apron or receiver are next placed inposition. When the driving mechanism is actuated after a supply ofpowdered emery is placed on the feed board, the sharpening 'or grindingaction progresses automatically as the vibration incident to theoperation of the machine feeds the abrasive and the reversed ratchetmechanism provides for the proper movement of the rotary cutters acrossthe ledger plate.

I claim: I

1. In a sharpening device for lawn mowers, a table, means for supportingthe lawn mower on the table, driving mechanism for the cutters of thelawn mower, and an inclined feed board supported on the table andarranged to feed an abrasive to the cutters under the action of thevibration set up by the moving parts of the device.

2. In a sharpening device for lawn mowers, a table, means for supportingthe lawn mower on the table, driving mechanism for the cutters of thelawn mower, an inclined feed board supported on the table and arrangedto feed an abrasive to the cutters under the action of the vibration setup by the moving arts of the device, and a receiver for col acting theabrasive after it has participated in the grinding action.

3. In a sharpening device for lawn mowers, a table, means for supportingthe lawn mower on the table, driving mechanism for the cutters of thelawn mower, an inclined feed board supported on the table and arrangedto feed an abrasive to the cutters under the action of the vibration setup by the moving parts of the device, said feed board being laterallyextensible and being releasably clamped in adjusted position.

4. In a sharpening device for lawn mowers, a table, means for supportingthe lawn mower on the table, driving mechanism for the cutters of thelawn mower, an inclined feed board supported on the table and arrangedto feed an abrasive to the cutters under the action of the vibration setup by the moving parts of the device, and a receiver for collecting theabrasive after it has participated in the grinding action, said receiverbeing laterally extensible.

5. In a sharpening device for lawn mowers having a gauge roller, atable, means for supporting the lawn mower on its roller on said tableincluding a bar fixed to the table and against which the auge rollerabuts and a ,chain engageable wlth the handle, and releasably connectedwith the table at points remote from said bar, and driving mechanism forthe lawn mower.

6. A sharpener for lawn mowers comprising a table upon which the lawnmower is mounted, means for maintaining said lawn mower in position onsaid table and driving mechanism for the cutters of said lawn mowerincluding an adjustable supporting arm, a driving pulley carriedthereby, means for actuating said driving pulley and a belt trained overthe driving pulley, and the ground wheel of the lawn mower.

7 A sharpener for lawn mowers including a table upon which said lawnmower is mounted, means for maintaining said lawn mower in position onsaid table, driving mechanism for the rotary cutter of the lawn mowerincluding a hand crank connected with the ground wheel and a foottreadle re-' leasably connected with the hand crank whereby the groundwheel may be selectively driven by hand or foot power.

JOHN ADAM GRASSN.

